Femto access points or alternatively femto base stations (femto BS) are lower-power, lower-cost, lower complexity cellular network base stations that may be installed by the user at home or small office environments for indoor coverage improvements and are typically connected through broadband connections such as cable modem to the operator's core network.
Since the femto base stations are (or will be) densely deployed, use of the typical cell search and cell selection methods, which are used for initial network entry/re-entry or handover for macro base stations in cellular networks, would be cumbersome and would result in extreme overhead in system operation and mobile station (MS) complexity and excessive power consumption. Furthermore, private femto base stations may be overloaded with signaling with unauthorized mobile stations trying to select them as target base stations for handover or system entry/re-entry.
Thus a need exists for an efficient method for femtocell discovery and association that would reduce the complexity and time of cell search and cell selection by mobile stations and thereby results in lower MS power consumption as well as helping to ensure that private femto base stations will not have to exchange signals and messages with unauthorized mobile stations thereby improving their performance.